A capacitor is a passive two-terminal electrical device used to store energy, and contains at least two electrodes separated by a dielectric region. The capacitance of a capacitor is proportional to the surface area of the electrodes, and inversely proportional to the thickness of the dielectric region. One type of capacitor is a metal-insulator-metal (MIM) capacitor. A MIM capacitor comprises an insulator sandwiched between two metal electrodes, and is formed within a back-end-of-line (BEOL) interconnect structure.